Shopify Developer & Design - product template + metafield system

We're an established UK online building-products retailer (large catalogue) levelling up our Shopify store, supplier by supplier. We're looking for a design-capable Shopify developer — someone who builds clean, well-structured Shopify and has a genuine eye for design. This first project builds the reusable foundation our whole catalogue will run on, then completes one product range (external cladding, ~11 products) as the gold-standard template.
What the project involves:

Set up a metafield + metaobject structure for product specs (material, colour, RAL, coverage, fire rating, dimensions, lead time, warranty) and per-brand info
Build one flexible, well-designed product + collection template that auto-renders spec tables, a brand block, swatches and a coverage calculator from those metafields
Configure storefront filters (Search & Discovery) from the metafields
Add Product/Review schema and handle canonical/robots on filter URLs (no URL/handle changes — existing handles stay)
Complete one cladding range end-to-end as the exemplar, including collection pages with auto-fill rules

You must be able to show:

Shopify metafield + metaobject experience
Storefront filtering (Search & Discovery or similar)
Liquid theme section development
A portfolio of stores that genuinely look good, not just function

Important: there's a design sign-off stage — you'll build the example product page in the template and we approve the look before go-live, as it becomes the template every other product inherits.
Strong work leads to ongoing rollout across the wider catalogue at an agreed per-range rate.
To apply, please include:

Two or three Shopify stores you've built (ideally large catalogues with filtering)
One line on how you'd structure metafields for a product that comes in multiple colours and sizes
Your availability and rough timeline for a project of this size